JPS6236256A - Sheet-head adjustment for printing device - Google Patents

Abstract

PURPOSE:To correctly adjust the head part of a sheet sent out from a feeding means by nipping said sheet between a transport roller until supported at two positions and discharging the sheet through reverse sending and again nipping the sheet onto the transport roll. CONSTITUTION:The edge part of a sheet P sent out one by one from a feeding means is nipped between a platen 19 and pressure roller 33 and 35, until supported at two positions. Then, the sheet P is discharged through reverse sending by reversely revolving the platen 19. The sheet P is curved as shown by the dotted line in the figure between a transport roller 137 and the platen 19, and the top edge of the sheet P uniformly contacts with the platen 19. Then, the sheet P is sent to a printing part consisting of a printing head 29, top edge guide 30 and the like by normally revolving the platen 19, and the sheet P is temporarily brought into stop, and printing of one line is carried out, and then the operation for the next line is carried out. Therefore, the ending of the head part of the sheet P is prevented and the sheet P is correctly resisted, and correct printing is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a sheet cueing method for a printing device such as a printer or a typewriter, in which a sheet such as printing paper is set at the printing position of the printing device.

[Technical background of the invention]

Generally, when printing on a plurality of sheets of paper continuously using a printing device such as a printer or a typewriter, a paper feed unit that automatically supplies the paper is attached to the paper feed port of the printing unit.

Some paper feeding units are equipped with a drive source, but
Recently, in order to reduce costs, some printers do not have a driving source, but instead obtain driving force from a printing unit to rotate a paper feed roller and feed sheets one by one to the printing unit.

Further, the printing unit grips the supplied paper between a platen and a pressure roller, supplies it to a printing position, and prints with a head that reciprocates along the platen.

An example of a printing device in which the driving force for the paper feed unit is obtained from the printing unit in this manner is disclosed in Japanese Patent Publication No. 58-6633.

In order to register the leading edge of the paper sent out by the paper feed roller, this printing device bends the paper by abutting the leading edge of the paper against the pressure contact between the platen and the pressure roller, and uses the stiffness of the paper to register the leading edge of the paper. are doing.

However, since the paper feed unit receives driving force from the print unit, when the paper feed roller is rotating, the platen must also rotate. On the other hand, in order to register the leading edge of the paper sent out by the paper feed roller, if the platen is rotated in the conveyance direction of the paper, the leading edge of the paper cannot be registered. For this reason, the platen is rotated in a direction opposite to the paper conveyance direction.

In other words, the paper sent out by the paper feed roller is brought into contact with the pressure roller between the platen and the pressure roller, which rotates in the opposite direction to the conveyance direction, and the paper is deflected to register the leading edge of the paper.Then, the platen is rotated in the normal direction. the paper is set in the print position.

[Problems with background technology]

However, because the paper is in contact with the press between the platen and the pressure roller, which rotate in the opposite direction to the conveyance direction,
Not only is the leading edge of the paper bounced and not registered accurately, but the leading edge of the paper is easily bent.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet cueing method for a printing device in which the leading edge of the paper is not easily bent during registration and can accurately register the leading edge of the paper.

[Summary of the invention]

Therefore, the present invention provides support for a sheet sent out by a paper feeding means such as a paper feeding roller at at least two locations in the transport direction between a first transporting means such as a platen and a second transporting means such as a pressure roller. After holding the sheet in its mouth until it reaches the printing position, the sheet is once retreated and ejected, and then the writing sheet is held between the first conveyance means and the second conveyance means, and the printing position is adjusted. The present invention provides a method for finding the beginning of a sheet in a printing device that feeds the sheet to the printer.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

The printing apparatus of this embodiment includes a printing unit 3 as shown in FIGS. 1 and 2 and a paper feeding unit 101 as shown in FIGS. 5 and 6.

First, the printing unit 3 has a structure as shown in FIGS. 1 to 4.

As shown in FIG. 1, a frame 9 is provided inside the cover 7 of the printing unit 3, and a platen shaft 13 is rotatably supported on both sides 9L, 9R of the frame 9 via bearings ILL, IIR. On the left side of this platen shaft 13 is a
A rotten knob 15L and a gear 17 are attached to the center, a platen 19 is attached to the center, and a gear 21 and a platen knob 15R are attached to the right side.

Further, a motor 23 for driving the platen 19 is attached to the side portion 9L of the frame 9, and the driving force of this motor 23 is transmitted to the gear 17 via gears 24 and 25.

Further, as shown in FIG. 2, guide rods 26, 28 are provided parallel to the platen 19. A head carriage 27 is attached to these guide rods 26, 28 so as to be able to reciprocate, and the head carriage 27 is driven laterally along the guide rods 26, 28 by a drive device (not shown). .

The print head 2 is mounted on the head carriage 27 as shown in FIG.
9. The tip guide 30 is attached, and the ribbon force sets 1 to 34 are detachable.

Furthermore, as shown in FIGS. 2 and 3, around the platen 19 are pressure rollers 33 and 35 arranged in two rows of platen guides 31, a paper pail roller 37 that presses the paper against the platen 19, and a platen cover 39. , a pair of coupling shafts 41 for coupling the paper feeding unit 101 to the printing unit 3, and the like are provided.

The pressure rollers 33, 35 are shown in FIGS. 1 and 3.
By rotating the pressure lever 43 shown in the figure about the shaft 42, the roller 44 rotates the arm 46 attached to the shaft 45, and the guide 31 rotates about the shaft 45, causing the platen 19 to rotate. Pressure is applied or pressure is released. Note that the arm 46 is attached to the roller 4 by a spring 48.
It is energized to 4.

Further, the paper pail roller 37 is connected to the paper pail lever 4
By rotating the arm 51, the arm 51 is rotated about the shaft 49, and the arm 51 is brought into pressure contact with the platen 19 or released from the pressure contact.

Note that a cover 53 can be opened and closed above the head carriage 27, and the ribbon cassette 34 can be replaced in the open state.

The paper feed/discharge port 5 of the printing unit 3 configured as described above has a paper feed unit 10 as shown in FIGS.
1 is installed.

This paper feeding unit 101 has side frames 103 on both sides.
(Only one side frame is shown in the figure) has an arc-shaped support portion 105 that engages with the coupling shaft 41.

Further, a lock lever 10 is provided on the outside of the side frame 103.
7 is pivotally supported at its intermediate portion by a shaft 109. This lock lever 107 fixes the paper feeding unit 101 to the coupling shaft 41 and includes a retaining portion 111 that engages with the coupling shaft 41.

Shafts 113 and 115 are attached to the rear of the side frame 103, and a guide 117 bent in an N-shape is attached. A paper feed frame 119 is detachably attached to the back of the guide 117. Further, a paper feed tray 121 is attached to the shaft 115, and rotates via a crank 125 when a set lever 123 is rotated, and a side plate 127 is slidable, so that paper of different sizes can be handled. ing.

A separation lever 131 is rotatably attached to the outside of the side plate 127 by a shaft 133 and has a separation claw 129 that separates the stacked sheets P one by one during feeding.

A paper feed roller 137 is attached to a shaft 135 supported by the side frame 103 above and in front of the paper feed table 121 .

A manual feed guide 139 and a guide 141 facing the guide 139 are provided in front of the paper feed tray 121, and the paper P sent out by the paper feed roller 137 is guided to the guide 117.
and 139, and also pass the manual paper through the guide 139.
and 141 to lead between the platen 19 and the platen guide 31.

Note that a paper ejection frame 143 is detachably attached to the manual feed guide 139.

A paper ejection roller 147 is attached to a shaft 145 on the guide 141, and a gear 149 is attached to one end and a sixth roller is attached to the other end.
A gear 151 is attached as shown in the figure. gear 149
A gear 153 is rotatably supported by a shaft 155 between the gear 21 and the gear 21 to connect the two.

Further, a paper ejection guide 157 is rotatable about a shaft 159 facing the paper ejection roller 147 .

As shown in FIG. 6, a gear 161 that meshes with a gear 151 and a gear 165 that meshes with a gear 163 are attached to the shaft 109.

Gear 163 is supported by shaft 167 and meshes with gear 169.

This gear 169 has a protrusion 171 inside and is supported by a shaft 175 together with a gear 173 as shown in FIG. A pipe 177 into which a shaft 175 is inserted is attached to the gear 173, and a coil spring 179 is fitted into the circumferential surface of the pipe 177. Note that this coil spring 179 is wound clockwise from the inside to the outside.

As shown in FIG. 8, a stop cam 183 having two protrusions 181 is fitted into the circumferential surface of the coil spring 179, and one end of the coil spring 179 is fixed.

A pipe 185 is attached to the gear 169, a shaft 175 is inserted into the pipe 185, and the pipe 185 is inserted into the coil spring 179.

That is, a spring clutch is interposed between gears 169 and 173, and a stop cam 183 is attached to this spring clutch.

A gear 187 is attached to the shaft 135, and this gear 187
is meshed with gear 173.

On the other hand, a stop lever 189 that engages with a protrusion 181 of a stop cam 183 is rotatably supported by a shaft 191 and biased downward by a spring 193.

In the above configuration, this printing device operates as follows.

As shown in FIG. 5, set the paper P on the paper feed table 121,
The set lever 123 is rotated to rotate the paper feed table 121 and press the paper P against the paper feed roller 137.

In such a state, when a print command is issued, the fourth
The slider carriage 27 shown in the figure moves from the left end home position to the center side and waits for paper to be supplied.

Further, the motor 23 shown in FIG. 1 is driven to rotate as shown in FIG. 9, and the platen shaft 13 shown in FIG. 5 is rotated clockwise. Therefore, the gear 149 also rotates clockwise via the gear 21.153. Therefore, the gear 151 shown in FIG. 6 attached to the other end of the shaft 145 of the gear 149 rotates counterclockwise (rotates in the same direction as the gear 149).

This rotation of gear 151 causes gears 161 and 165 to rotate clockwise, and gear 163 meshing with gear 165 to rotate counterclockwise. This causes gear 169 to rotate clockwise. This causes the pipe 177 to rotate. At that time, as shown in Figure 8, the spring 17
The protrusion 18 of the stop cam 183 holding one end of 9
1 is locked by the stop lever 189, the pipe 185 idles inside the spring 179. When the rotation of the gear 169 further progresses and the protrusion 171 pushes up the stop lever 189, the stop cam 183 is unlocked and the pipe 185 and the spring 179 are connected.
A pipe 177 connected to this spring 179 rotates.

For this reason, the gear 173 fixed to this pipe 177
rotates clockwise.

As a result, the gear 187 rotates to the left, so that the paper feed slot 137 shown in FIG. 5, which is attached to the shaft 135, rotates to the right. For this reason, the paper P is sent out, the paper P gets caught on the separation claw 129 and bends, and when it exceeds the elastic limit, it bounces and becomes 1
The paper is separated into sheets and enters between the platen 19 and the pressure roller 33 along guides 117 and 139.

Then, as shown in FIG. 10, the motor 23 is stopped after a predetermined amount of M1 rotations that will cause the paper P to be caught between the platen 19 and the pressure rollers 33, 35. Then, the motor 23 is reversely rotated by a predetermined amount M2.

As a result, the platen 19 rotating in the opposite direction moves the paper P backward, and the paper P is ejected from the platen 19 and the pressure roller 33.

As the platen shaft 13 rotates in the opposite direction, the gear 169 also rotates in the opposite direction. As a result, the pipe 185 also rotates in the opposite direction, but the spring 179
Since the pipe 185 is rotating in the opening direction, the rotational force of the pipe 185 does not reach the pipe 177 by one inch. Therefore, platen 1
Even if 9 is rotated in the reverse direction, the gear does not rotate and the paper feed roller 137 also does not rotate.

In this state, when the paper P is ejected from between the platen 19 and the pressure roller 33, since the rear side of the paper is held down by the paper feed roller 137, the paper P is pushed to the platen 19 as shown by the broken line in FIG. and paper feed roller 137
Due to the stiffness of the paper P, the leading edge of the paper P is registered at the pressure contact portion between the platen 19 and the pressure roller 33.

Then, the motor 23 is rotated in the normal direction again, the paper P is again gripped by the platen 1.9 and the pressure roller 33.35, and the paper P is fed by a predetermined amount. When the motor 23 has rotated by a predetermined amount M3, that is, printing of the paper P starts. The motor 23 is temporarily stopped at this position, and the print head 29 located at the center side is
is returned to the home position on the left side by movement of the carriage 27, and printing is started. -The platen rotates by one line each time printing of each line is completed.

The printed paper P is transferred to the paper ejection roller 35 and the paper ejection guide 157.
It is discharged through which space.

The leading edge of the paper P to be discharged rises along the manual feed guide 139 and the paper discharge frame 143, and when the trailing edge of the paper P is discharged, the trailing edge of the paper is supported by the recess of the guide 141 and placed in the paper discharge stacker. be accommodated.

By the way, while the protrusion 171 comes off the stop lever 189 and the tip of the lever 189 falls onto the circumferential surface of the stop cam 183 and continues to rotate, the paper feed roller 137 feeds out the paper P. When the tip of the stop lever 189 engages with the protrusion 181 of the stop cam 183, the pipe 185 idles within the spring 179, and the gear 173 stops rotating.

When the projection 171 pushes up the lever 189 again, the paper is fed. This cycle is repeated, and the paper P is automatically sent out at a constant cycle.

The above embodiment provides the following effects.

(1) After the paper sent out by the paper feed roller 137 is gripped between the platen 19 and the pressure roller 33.35, the paper is moved back and registered, so that when the paper is gripped, the conveyance The paper is fed between the platen 19 and the pressure roller 33, which are rotating in the direction, so that the paper is smoothly held in the
, the leading edge of the paper is hard to bend.

(2) The stacked sheets are transported by the feeding roller 137.
The paper is fed out sheet by sheet, and the fed paper is placed on the platen 19.
After the paper is held between the two rows of pressure rollers 33 and 35 arranged side by side in the circumferential direction of the platen 19, the paper is once retreated and discharged in order to register the leading edge of the paper. Pressure roller 33.3
5 discharges the paper while supporting it at multiple locations, the pressure rollers 33 and 35 are less likely to slip on the paper, and the paper does not remain stuck in its mouth without being discharged from the pressure opening roller 33. .

Therefore, the ejected paper reliably forms a bend (loop) and is reliably registered at the pressure contact portion between the platen 19 and the pressure roller 33.

(3) After the motor 23 has rotated by a predetermined amount M1 after the motor 23 starts rotating, the motor 23 is rotated in the opposite direction to register the paper P, so that the paper can be ejected without the need for a paper edge detection means such as a sensor; Can be resisted.

Therefore, this cueing method can be applied even to a printing device in which the printing unit 3 is not provided with a sensor for detecting the leading edge of the paper held between the platen 19 and the pressure rollers 33, 35.

That is, it is possible to cue up the print unit 3 without having to worry about the format of the printing unit 3.

[Modified example]

The present invention is not limited to the above-mentioned embodiment, and for example, the following modifications are possible.

(1) In the above embodiment, a printing device is shown in which the printing unit and the paper feeding unit are detachable, but the printing unit and the paper feeding unit may be integrated.

(2) In the above embodiment, after the platen 19 rotates and feeds the paper by the paper feed roller 137, the motor 23 is rotated by a predetermined amount M2 after rotating by a predetermined amount M1, and the pressure roller 3
3.35 and the platen 19 are discharging the paper held in their mouths, but a sensor is provided at the tip of the pressure roller 35,
When this sensor detects the leading edge of the paper, the platen 19 may be reversed.

(3) As shown in FIG. 11, two or more pressure rollers 203.20
5.207 may be pressed against the platen 209.

In this case, the paper may be held up to the pressure roller 205 and then retreated to be discharged, or may be held up to the pressure roller 207 and then discharged.

(4) In the above embodiment, the platen 19 is driven and the pressure rollers 33.35 are driven, but the pressure rollers 203, 205, 207 may be driven and the platen 209 is driven as shown in FIG. .

Also, the platen 209 and pressure rollers 203 and 205
．． 207 may be driven together.

(5) This invention is based on the platen 211 as shown in FIG.
is fixed, and the present invention can also be applied to a printing device in which paper guided by a guide 213 is fed to a printing position by rollers 215, 217, 219, and 221.

(6) In this invention, as shown in FIG. 13, the guide 223.
The paper guided by 225 is transferred to rollers 227 and 229.
．． The present invention can also be applied to a printing device that supplies the print position of the platen 235 using 231 and 233.

〔Effect of the invention〕

As explained above, according to the present invention, the stacked sheets are fed out one by one by the feeding means, and the fed sheets are placed between the first conveying means and the second conveying means which are pressed into contact with each other. In a printing device that carries out printing work by holding the sheet in its mouth and supporting it at multiple locations in the conveying direction and feeding it to a printing position, the sheet fed out by the feeding means is placed between the first conveying means and the second conveying means. After holding the sheet in its mouth to a position where it is supported at at least two places in the conveying direction, the sheet is once retreated and discharged, and then the sheet is held between the first conveying means and the second conveying means again. Since the leading edge of the paper is not easily bent during registration, and the leading edge of the paper can be accurately registered, it is possible to obtain a sheet cueing method for a printing device that can accurately register the leading edge of the paper. .

[Brief explanation of drawings]

Figures 1 to 4 are diagrams showing the configuration of the printing unit.
2 is a cross-sectional view of the printing unit, FIG. 2 is a longitudinal sectional view of the printing unit, FIG. 3 is a sectional view showing a pressure roller pressure contact mechanism, and FIG. 4 is a view showing the structure around the print head. Figures 5 to 8 are diagrams showing the configuration of the paper feeding unit.
The figure is a vertical sectional view showing the overall configuration of the paper feed unit l-'.
The figure shows a drive transmission mechanism provided on the left side frame, and FIGS. 7 and 8 are cross-sectional views showing the structure around the spring clutch. FIG. 9 is a timing chart for explaining the operation, and FIG. 10 is a diagram for explaining the operation. FIGS. 11 to 13 are diagrams showing modifications of the present invention. 3...Print unit 19...Platen 29...Print head 33.35...Pressure roller 101...
・Paper feed unit 137...Paper feed roller 147・
... Paper ejection roller 2/Figure 1 5 ノ, 2-Figure 1/? J-1f Inasano 3 Mua

Claims (5)

[Claims] (1) The stacked sheets are fed out one by one by the feeding means, and the fed sheets are held between the first conveying means and the second conveying means, which are pressed together, at multiple locations in the conveying direction. In a printing device that supports and sends the sheet to a printing position for printing work, the sheet sent out by the feeding means is supported at at least two places in the transport direction between the first transporting means and the second transporting means. After gripping the sheet to the printing position, the sheet is once retreated and discharged, and then the sheet is gripped again between the first conveying means and the second conveying means, and the sheet is moved to the printing position. A method for locating a sheet in a printing device, characterized in that the sheet is sent to. (2) In the sheet cueing method for a printing device according to claim 1, the first conveying means is a platen, and the second conveying means is a plurality of sheets arranged in a circumferential direction of the platen. A sheet cueing method for a printing device characterized by using a pressure roller. (3) In the sheet cueing method for a printing device according to claim 1, the first conveyance means and the second conveyance means are a plurality of pairs of rollers pressed against each other. How to find the beginning of a sheet in a printing device. (4) In the sheet cueing method for a printing device according to claim 1, the first conveying means is driven by a drive source, and the second conveying means is driven by the operation of the first conveying means. A sheet cueing method for a printing device characterized by being driven. (5) In the sheet cueing method for a printing device according to claim 1, the second conveying means is driven by a drive source, and the first conveying means is driven by the operation of the second conveying means. A sheet cueing method for a printing device characterized by being driven.